Henry,
I never blew any of the sweep tubes either but I was also pretty darned
careful as didn't have a lot of money to go spending on my mistakes.
but, I sure do know a lot of people who really went through those
tubes.
I remember one of the local ham radio stores used to have a tube on
their shelf where everybody could see it. One side was all caved in
and I guess pretty darned ugly. Just a reminder of what could happen
if you weren't careful with one of those rigs.
Don W6SMB
On Fri, 22 Nov 2002 09:51:38 -0000, Henry Brugsch wrote:
>Hi Don, well I owned an ft101-e for about ten years, never replaced the
>sweep tubes. Now, I am working with an ft101-z, and a ts440. The latter is
>equipped with an auto-tuner. Butch, it still works, now.
>The 101-z has hooked up to it a palomar tuner-tuner, which is essentially a
>pre-tuned noise bridge to 50 ohms. Adjust the atu for maximum quiet. Another
>problem with this little gem is, if the fuse blows, you get incorrect
>readings, but no way of really knowing that your device is off the air.
>So, you really need to be careful.
>----- Original Message -----
>From: "Don Bishop" <[log in to unmask]>
>To: <[log in to unmask]>
>Sent: Friday, November 22, 2002 12:16 AM
>Subject: Re: tuning up an antenna
>
>
>> Hi,
>>
>> You sure can use a noise bridge to tune an antenna tuner. Just make
>> sure you know where the 50 ohm setting is on the bridge and then tune
>> the tuner for a sharp null in the noise. One caution: be darned sure
>> you remove the bridge from the line before you transmit or you will
>> have a noise bridge that doesn't produce a sound!
>>
>> If you are using one of the rigs of today with an automatic antenna
>> tuner you can tune by listening to the motor and when it stops, the
>> antenna is matched. You don't know how good the match is of course,
>> but it's a way to do it without a lot of hightech equipment. When you
>> do this without any speech or similar readout, it isn't a bad idea to
>> move up and down the band a bit just to get an idea of how much your
>> swr is changing as you shift frequency. Once you get one of these
>> things tuned up on a band, it really is a good idea to check the match
>> with the auto antenna tuner whenever you change frequency very much.
>>
>> I do remember the rigs with a sweep tube amplifier. They weren't quite
>> as forgiving with swr and it was always a good idea to tune the thing,
>> regardless of how you did it, very promptly. If you didn't, you really
>> needed a good supply of new tubes. <grin> Those things could blow in
>> a hurry if you weren't careful.
>>
>> Don W6SMB
>>
>>
>>
>> On Thu, 21 Nov 2002 19:17:41 -03-30, Michael Ryan wrote:
>>
>> >Can a noise bridge which was once used on an old heath kit
>> >HW-12 be used in conjunction with an antenna tuner for reading SWR?
>> >I will try and describe it.
>> >It has a switch on the lower front which slides back and forth to the
>left
>> >or right for turning on or off and a flat roguery knob next to the
>> >switch. The connectors for antenna and so on are on the top. It also
>has
>> >a round raised speaker.
>> >I would also like to know what to look for, when it comes to the power
>> >supply hum, when the rig is loaded up for maximum out put.
>> >
>> >Thanks all:
>> >Michael
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